Exercise and inflammation-related epigenetic modifications: focus on DNA methylation.

Epigenetics is the study of mitotically or meiotically heritable phenotypes that occur as a result of modifications to DNA, thereby regulating gene expression independently of changes in base sequence due to manipulation of the chromatin structure. These modifications occur through a variety of mechanisms, such as DNA methylation, post-translational histone modifications, and non-coding RNAs, and can cause transcriptional suppression or activation depending on the location within the gene. Environmental stimuli, such as diet and exercise, are thought to be able to regulate these mechanisms, with inflammation as a probable contributory factor. Research into these areas is still in its infancy however. This review will focus on DNA methylation in the context of inflammation (both pro- and anti-inflammatory processes) and exercise. The complexity and relative shortcomings of some existing techniques for studying epigenetics will be highlighted, and recommendations for future study approaches made.